CodeIgniter 4 Deferable Features

It means the validation remains strongly tied with POST variables? I am not sure this is okay... for example if we get data from an external API or from CLI or anywhere else we can't use the built in validation for these types of data...

http://www.codeigniter.com/user_guide/li...-than-post

Thank you for pointing out to this feature, I didn't know about it, but it's not exactly what I thought how to achieve validate data of any source: usually validation belongs to the models certain fw apply validation on setting the variable, certain validates the data on save (insert/update). Something like this is on the roadmap or discussed?